Plastic rail assemblies, for example for use in fencing and decking, are gaining popularity due to their durability and pleasant appearance. Unlike wood used in conventional fencing or decking rail assemblies, the plastic components, typically made of polyvinyl chloride (PVC), do not require post-sale painting and weatherproofing and will not rot over time. Rail assemblies feature horizontal rails, or sloped rails when used as a stair railing, supported on and extending between vertical posts spaced apart along a straight line. Hollow PVC posts are fitted over and supported around rigid pipes that provide the necessary strength to support the final structure in a stable and reliable manner over time. The rigid pipe may be supported by driving a lower end thereof a distance into the ground or by anchoring it to some kind of foundation or support surface that is provided on, in, or above the ground. Different devices have been developed for positioning the hollow post about the pipe for each of these situations.
A recognized issue with the use of hollow posts in this manner is that the walls of the hollow post are relatively thin, especially compared to a conventional solid wood post, and accordingly when screw-type fasteners are used to attach a rail or other component to the hollow post, the depth of material available for engagement in the axial direction of the fastener is minimal. As a result, screwing the rail to the hollow post alone is often insufficient to establish a desired or required level of strength and durability for this connection, especially where the rail is expected to bear the weight of pickets, panels, studs, or other components of the overall railing structure, particularly any components that are not light-weight plastic, or where the rail is intended to act as a protective barrier that is expected to be able to prevent a fall from an elevated area bound one or more sides by the railing structure or bear, or act as hand railing providing for providing support of a user while traversing a series of steps.
Previous solutions to this problem have been proposed, each involving the mounting of a fixture onto the pipe to present additional sections of fastener-engagable material at a distance outward from the pipe just inside the hollow post placed thereover. Examples of these solutions are listed as follows.
U.S. Pat. No. 7,137,230 teaches a device that is designed to fit over an upright pipe at an intermediate location therealong to present planar metal flanges a short distance outward therefrom to brace against planar walls of a hollow post and provide additional material for screws to bite into when attaching rails, studs or the like to the post.
U.S. Pat. No. 7,455,282 teaches a device having a socket at its lower end arranged to seat atop an upright pipe around which a hollow post is to be supported, and a rectangular upper portion presenting four planar walls to brace against planar walls of a hollow post and provide additional material for screws to bite into when attaching rails to the post.
U.S. Pat. No. 7,530,550 teaches a device having a tubular body for fitting over an upright of rectangular cross-section, and pairs of mounting panels connected to the tubular body and extending therefrom to present resilient sections adjacent the inside of a hollow post to be fitted over the upright in order to receive and retains fasteners driven through the walls of the post.
Each of the forgoing prior art solutions appears to have a shortcoming in that the fastener-engagable fixture residing inside the hollow post is mounted directly on the upright pipe, and so the absolute position of the parts of the fixture that are intended to rest just inside the hollow post are is dictated by the position and orientation of the upright pipe.
Applicant's U.S. Pat. No. 7,739,796, the entirety of which is incorporated herein by reference, teaches multi-piece mounting devices shown in FIGS. 8 to 11 thereof that each allow repositioning of the outer periphery of an outermost piece of the device relative to the pipe on which the innermost piece is mounted by disengaging the outermost piece from the innermost piece and then re-engaging these pieces together in a different one of a number of selectable relative positions therebetween, thereby allowing a user to set the final position of the outer periphery of the device relative to the pipe to as to be able to adjust the final position of the post that is in turn fitted over the outermost piece around the pipe. Accordingly, the user can use one of these devices at a distance upward from the a supported bottom portion of the post, which may be supported by a mounting device of the same or different type, to select a degree of relative alignment between the axis of the pipe and the axis of the post, for example to allow a vertical orientation of the post on a pipe that may be angled somewhat out of an entirely vertical orientation.
With further reference to FIG. 12 thereof, Applicant's same patent also teaches a one-piece mounting device that allows for similar angular adjustment between the pipe and the hollow post to be mounted thereover. This device includes a tubular portion defining an opening of uniform cross-section having one dimension selected to slightly exceed the pipe's outer diameter, and the other dimension selected to significantly exceed the first, giving the opening an elongated shape. A cylindrical outer wall of is carried around the tubular central portion at a distance outward therefrom by a webbing, and features a circular outer periphery and an axial height spanning only a part of the tubular portion's length. The opening is placed over the pipe, and its elongated dimension allows shifting of the piece back and forth in radial directions relative to the pipe axis to allow user-controlled positioning of the outer cylindrical wall relative to the pipe axis, before fastening of the part of the tubular portion that is not concealed by the outer wall to the pipe.
The prior art hollow post rail attachment solutions referenced above are not compatible with the Applicant's system for selective angling between the pipe and the hollow post to be mounted thereon, as they attach directly to the pipe and have fixed dimensions and thus only fit within the hollow post if the post is installed in a prescribed position concentric with the pipe.
Accordingly, Applicant has developed new methods and apparatuses for providing additional screw-engagable material inside a hollow post in a manner that is compatable with the aforementioned devices for setting the post position/angle relative the upright pipe.